1. Field of the Invention
The present invention relates generally to treadmills, and more particularly, to a collapsible treadmill capable of being automatically secured to a collapsed position while at the collapsed position.
2. Description of the Related Art
A conventional treadmill is composed of a base and a treadbase pivotably mounted on the base to enable the treadbase to pivot relative to the base between a horizontal operative position and an upright or slantingly standing collapsed position such that the required space occupied by the treadmill can be reduced when the treadmill is not in use.
The aforesaid treadmill must have a positioning device for securing the treadbase to a collapsed position. For example, Taiwan Utility Model Publication Nos. 472595 and 395263 disclosed that the treadbase would be automatically secured to a collapsed position while the treadmill is at the collapsed position.
The treadmill disclosed in Taiwan Utility Model Publication No. 472595 is primarily composed of a base, a treadbase, a retractable bar assembly, and a stopping member. The retractable bar assembly includes a cylinder and a bar respectively pivotably connected with the treadbase and the base. The stopping member is pivotably mounted on the base at an end thereof together coaxially with the bar. The stopping member will be automatically inclined by means of the gravity while the treadmill is at a collapsed position so as to engage against an end surface of the cylinder, thereby securing the treadbase to the collapsed position. However, this conventional treadmill is unsafe, i.e. the stopping member is too large-sized, and no available mechanical power is provided to maintain the engagement of the stopping member to the end surface of the cylinder, such that it's easy for the user to touch the stopping member carelessly and to further cause the stopping member to run away from where the stopping member engages against the end surface of the cylinder, thereby causing the treadbase to topple down.
The treadmill disclosed in Taiwan Utility Model Publication No. 395263 is primarily composed of a base, a treadbase, a pneumatic cylinder, a support piece, and a torsion spring. The pneumatic cylinder includes a cylinder and a bar respectively pivotably connected with the base and the treadbase. The support piece, the torsion spring, and the bar are coaxially pivotably connected to the treadbase. While the treadbase is at a collapsed position, the support piece will automatically engage against the end surface of the cylinder by means of the resilience generated by the spring so as to secure the treadbase to the collapsed position and meanwhile to keep the support piece engaging against the end surface of the cylinder by the spring. Although the torsion spring can keep the support piece engaging against the end surface of the cylinder, the support piece is still too large-sized such that it's easy for the user to touch the stopping member carelessly so as to cause the support piece to run away from where the support piece engages against the end surface of the cylinder and to further cause the treadbase to topple down. Hence, such kind of treadmill is still unsafe.